Sergeant Ray Wylie, police alcohol harm prevention officer for the Eastern District, said the party organisers were misinforming young people.
A law change in 2012 made it illegal to give under-18s alcohol without parental consent. The Sale and Supply of Alcohol Act also required alcohol supplied to minors to be served in a responsible manner and in a safe environment.
The person supplying the alcohol must be either the parent or legal guardian, or have express consent of a parent or guardian.
Wylie said the party could have led to dangerous consequences.
"At previous events of this type, we have seen young teenagers dangerously intoxicated to the point where they are unable to look after themselves," Wylie said.
"We encourage organisers to run parties without the inclusion of alcohol and encourage parents to take the same approach when choosing whether their child should attend.
"The organiser appears to be confusing his audience around the legalities of this event by including a reference to permission slips from parents." Wylie warned that permission slips would not save anyone from an instant fine of $200 for being an unaccompanied minor consuming or possessing alcohol in a public place.
Police said the organiser claimed to have made thousands of dollars in the sales of tickets and had told authorities he would not be making any refunds.
As a result, police warned people not to spend money on anything distributed via social media - "particularly one with so many red flags".
The Facebook page set up to entice young people to the event has also been taken down.
However, police acknowledge that there may well still be advertising going on off the internet and are warning parents to be vigilant about it.
"It would be highly disappointing to think that parents would knowingly allow their child to head off from home to an event like this involving alcohol," said Wylie.
"We work hard to prevent harm to young people every day and will do everything we can to prevent them getting into an unsafe situation due to alcohol."
- Staff reporter, Hawke's Bay Today